Toward the end of the season last year, when boondocking I started having a problem with my lights flickering very badly when running the water pump in my travel trailer. I assumed that my batteries were failing so I replaced them. The problem did not go away. I checked all of the wiring that is accessible and cleaned all of the connections including grounds. Still flickering. I thought maybe the pump was drawing too many amps or shorting out so I replaced it with a new one. Lights are still flickering. The lights have always flickered a little when the pump runs but now almost go out. Even when the batteries are fully charged this happens. The idiot lights on the control panel drop all the way into the red but immediately go back to green when the pump stops. I'm just wondering if anyone out there has any ideas about what the problem might be? Just to be clear, the trailer is pretty old (1989).